The Duct Leakage test
Rhode Island has adopted the 2013 State Energy Conservation Code. The Code as written requires all new residential HVAC systems (new home or an existing home) with ductwork in unconditioned (uninsulated) spaces to be tested for air tightness. This test is called “duct leakage to the outside test”. This requirement is not new. It was first introduced in 2010. The test results are to be reported to the building official in the form of cubic feet of air per minute (CFM) leakage per 100 square feet of conditioned (insulated) space at 25 pascals of pressure (CFM25). Note: If all ducts and air handlers are located within the thermal envelope (conditioned space) testing may not be required. Check with the local building official.
Duct leakage to the outside test ?
This test is designed to quantify the amount of air that is lost through ductwork located outside the homes conditioned space, such as an unheated basement, attic or crawlspace. Air leaks inside the conditioned space are not considered as bad and therefore are not considered as part of the test. Although, the system balance and overall comfort of the home may be effected.
When should the test be performed?
Most test are performed either immediately after HVAC rough-in is complete or when the home is entirely finished.
Who is approved to perform a duct leakage test?
The building code states that testing will be performed by an approved third party where required by the building official. The Building Code Commission is reviewing legislation that will approve statewide credentials. As of today there is no standard in place. The builder is not allowed to perform the test.
Is a duct leakage test required for a gut rehab?
As a rule, if the cost of any new ductwork is less than 50% of the entire existing system cost, then the test requirement may be waived by the local building official.